Hello again!

I have a researcher who has made a digoxygenin labeled, single stranded DNA probe that is 650 bp.  I am having trouble getting it to work on tissue sections (negative results).  We have done a dot blot test so we know that the dig, biotinylated anti-dig, streptavidin AP and substrate are working.  Could it be this is just too big to penetrate into the tissue sections?

We digested the tissue with Proteinase K, acetylated with acetic anhydride in TEA buffer, hybridized overnight at 37 degrees C, and used the InnoGenex Universal ISH kit for dig-labeled probes for detection.

Thanks in advance,

Teri Johnson
Managing Director Histology Facility
Stowers Institute for Medical Research
1000 E. 50th St.
Kansas City, Missouri  64110
tjj@stowers-institute.org